Ten Lessons in Public Health: Inspiration for Tomorrow's Leaders

2. Get into the Field

7 While our home was in Dacca, my work was “in the field.” I wasn’t sent to Pakistan to live the good life in a compound but to learn how cholera, that rapidly lethal diarrheal disease, spread and to test new vaccines to prevent it. Cholera would occasionally break out of its historical home, the fetid delta regions of the Indian subcontinent. Such was the case in the 1960s. Sporadic outbreaks began occurring elsewhere in Asia, and also in Africa and even the Americas. U.S. health planners were concerned that it might be only a matter of time before cholera invaded the United States. With our Southeast Asia Treaty Organization (SEATO) allies, the United States had created a major research program at the Cholera Research Laboratory (CRL) in East Pakistan. Its headquarters, laboratory, and main hospital were located in Dacca, the capital; a field hospital and study population of 250,000 were centered on Matlab Bazaar, a rural market town. The trip there took one hour in a hot, LESSON 2 GET INTO THE FIELD A problem must be such that it matters what the answer is—whether to science generally or to mankind. peter medawar 8 TEN LESSONS IN PUBLIC HEALTH cramped, un-air-conditioned Chevrolet Blazer, plus three hours—far more pleasant—by speedboat. On those car rides I silently cursed the stateside bureaucrat who, never having worked in the tropics, saved a couple hundred dollars by buying the program a vehicle without air conditioning and with only two doors (and thus only two windows to roll down). CRL was staffed by Bengali and (largely U.S.) expatriate scientists. Half were employed by the National Institutes of Health (NIH), to study the mechanisms by which cholera infection caused dehydrating diarrhea, and half by the CDC, to test the effectiveness of cholera vaccines. The villages around Matlab Bazaar were, quite literally, dirt poor. Except for a rare wooden house or tin roof, almost all the homes were made of mud and daub, with thatched roofs. The poorer homes were always crumbling (the mud walls needed to be replaced annually after the monsoon rains). None of the dwellings had running water. Cows, chickens, water buffalo, and goats competed with humans for living space. The only sources of truly potable water were occasional (and only occasionally working) hand-pumped artesian wells. Most drinking water was drawn from polluted ponds and open wells. Despite their profound poverty, the villages were startlingly neat and clean. Each species of animal (excepting the chickens) occupied its own place. Human waste was deposited in the fields or at the edge of a pond, never in the living areas. The floors of the huts were under constant maintenance , kept smooth by regular applications of fresh mud. The entire study population was carefully monitored for diarrhea; any suspected cases of cholera were quickly transported by speedboat to the Matlab hospital. In cases of cholera, time is of the essence. The diarrhea that is cholera’s hallmark can rapidly dehydrate a patient, resulting in coma and cardiovascular collapse within hours. Patients routinely GET INTO THE FIELD 9 arrived at the hospital having lost more than 10 percent of their body weight. Shriveled and shrunken, with a barely perceptible pulse, they often appeared dead on arrival, but replacing lost body fluids quickly revived them, convincing more than one villager that we literally raised people from the dead. Possibly my saddest experiences were the times I had to explain to distraught mothers, who often had traveled great distances carrying unresponsive children in their arms, that we did not perform miracles and could not bring their dead son or daughter back to life. At that time the available cholera vaccines were entirely useless, yet national authorities throughout the developing world insisted that all visitors be vaccinated before they entered the country. There being no viable vaccine worth testing —one of the program’s assignments—I instead investigated the ways in which cholera spread, hoping to find clues that might tell us how to stop it early. This was classical epidemiology . One of the first things I wondered about was whether the regular use of pathogen-free artesian well water (when available ), instead of inevitably polluted local pond water, really lessened the risk of contracting cholera (as one might expect, but should never assume without testing). Billy Woodward, the CDC epidemiologist who had preceded me, spent three years carefully...